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1.
Bioorg Med Chem ; 73: 117004, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36148773

RESUMO

A series of ciprofloxacin-uracil conjugates 5a-t were synthesized and identified by 1H NMR, 13C NMR, mass spectroscopy and elemental analyses. The antibacterial results revealed that the new derivatives exhibited better activity against Gram-positive than the Gram-negative strains; most of the target compounds exhibited good activities against S. aureus ATCC 6538. Compounds 5b and 5g possess the highest activities with MICs of 1.25 and 2.37 µM, respectively, which are more potent than the parent drug ciprofloxacin, MIC, 7.58 µM. In addition, they also exhibited potent activities against MRSA AUMC 261 with MICs, 0.031 and 0.046 µM respectively, higher than ciprofloxacin with MIC, 0.57 µM. Moreover, compounds 5b and 5g showed potent inhibitory activities against DNA gyrase (IC50 = 1.72 and 5.72 µM) and topoisomerase IV (4.36 and 7.77 µM) compared to ciprofloxacin with IC50 values 0.66 and 8.16 µM, respectively. The molecular docking study revealed that compounds 5b and 5g may formed stable interaction with the active sites of DNA gyrase and topoisomerase IV similar to ciprofloxacin. Hence, 5b and 5g are considered promising antibacterial candidated against MRSA AUMC 261 strains that requires further optimization.


Assuntos
DNA Girase , Staphylococcus aureus Resistente à Meticilina , Antibacterianos/química , Antibacterianos/farmacologia , Ciprofloxacina/farmacologia , DNA Girase/genética , DNA Topoisomerase IV , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Staphylococcus aureus , Inibidores da Topoisomerase II/química , Inibidores da Topoisomerase II/farmacologia , Uracila
2.
Molecules ; 27(19)2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36234905

RESUMO

An appropriate and efficient Q-tube-assisted ammonium acetate-mediated protocol for the assembly of the hitherto unreported 5-arylazopyrazolo[3,4-b]pyridines was demonstrated. This methodology comprises the cyclocondensation reaction of 5-amino-2-phenyl-4H-pyrazol-3-one with an assortment of arylhydrazonals in an NH4OAc/AcOH buffer solution operating a Q-tube reactor. This versatile protocol exhibited several outstanding merits: easy work-up, mild conditions, scalability, broad substrate scope, safety (the Q-tube kit is simply for pressing and sealing), and a high atom economy. Consequently, performing such reactions under elevated pressures and utilizing the Q-tube reactor seemed preferable for achieving the required products in comparison to the conventional conditions. Diverse spectroscopic methods and X-ray single-crystal techniques were applied to confirm the proposed structure of the targeted compounds.


Assuntos
Piridinas , Catálise , Técnicas de Química Sintética , Piridinas/química
3.
J Org Chem ; 85(23): 15368-15381, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33147024

RESUMO

An appropriate and efficient Q-tube-assisted palladium-catalyzed strategy for the synthesis of novel, unparalleled diaza-dibenzo[a,e]azulene and diaza-benzo[a]fluorene derivatives has been sophisticated, which includes oxygen and AcOH-induced oxidative C(sp3)-C(sp2) cross-dehydrogenative coupling reactions of 1-amino-2-imino-4-arylpyridine-3-carbonitriles with benzocyclic ketones such as benzosuberone, tetralone, thiochromone, and chromone, respectively. This Q-tube gas purging kit assisted-protocol features safe due to easy pressing and sealing, a wide substrate scope, easy workup and purifying phases, and the use of O2 as a benign oxidant, in addition to being scalable and having a high atom economy. The suggested mechanistic pathway includes a formal dehydrative step followed by palladium AcOH-induced CH(sp3)-CH(sp2) oxidative cross-coupling. In this study, X-ray crystallographic analysis has been used to authenticate the targeted products.

4.
BMC Palliat Care ; 19(1): 48, 2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-32290860

RESUMO

BACKGROUND: Volunteers play a significant role in supporting hospice and palliative care in Africa, but little is known about the types of volunteers, their motivations and roles in service delivery. METHODS: Palliative care experts from 30 African countries were invited to participate in an online survey, conducted in English and French, that consisted of 58 questions on: socio-demographics, the activities, motivation and coordination of volunteers, and an appraisal of recent developments in volunteering. The questionnaire was pre-tested in Uganda. Quantitative data was analysed descriptively with SPSS v22; answers on open-ended questions were analysed using content analysis. RESULTS: Twenty-five respondents from 21 countries replied to the questionnaire. The typical volunteer was reported to be a female aged between 30 and 50 years. Volunteer roles included, among others: direct patient assistance, providing psychosocial / spiritual support, and assisting patients' families. Respondents considered altruism, civic engagement and personal gain (for a professional career) as volunteers' most significant motivational drivers. One in two respondents noted that recruiting volunteers is easy, and cooperation with the communities was often mentioned as helpful. Trainings mostly occurred before the first assignment, with topics covering the palliative care concept, care, psychosocial support and team work. Half of respondents described recent overall volunteering developments as positive, while the other half described problems primarily with financing and motivation. Most volunteers received transportation allowances or bicycles; some received monetary compensation. CONCLUSIONS: The findings show a wide range of volunteering in palliative care. We identified volunteers as typically 30-50 years old, non-professional females, motivated by altruism, a sense of civic engagement and personal gain. Palliative care services benefit from volunteers who take on high workloads and are close to the patients. The main challenges for volunteer programmes are funding and the long-term motivation of volunteers.


Assuntos
Motivação , Cuidados Paliativos/tendências , Voluntários/psicologia , Adulto , África , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Paliativos/métodos , Cuidados Paliativos/psicologia , Inquéritos e Questionários , Voluntários/estatística & dados numéricos
5.
J Med Syst ; 42(9): 162, 2018 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-30043178

RESUMO

The study of electroencephalography (EEG) signals is not a new topic. However, the analysis of human emotions upon exposure to music considered as important direction. Although distributed in various academic databases, research on this concept is limited. To extend research in this area, the researchers explored and analysed the academic articles published within the mentioned scope. Thus, in this paper a systematic review is carried out to map and draw the research scenery for EEG human emotion into a taxonomy. Systematically searched all articles about the, EEG human emotion based music in three main databases: ScienceDirect, Web of Science and IEEE Xplore from 1999 to 2016. These databases feature academic studies that used EEG to measure brain signals, with a focus on the effects of music on human emotions. The screening and filtering of articles were performed in three iterations. In the first iteration, duplicate articles were excluded. In the second iteration, the articles were filtered according to their titles and abstracts, and articles outside of the scope of our domain were excluded. In the third iteration, the articles were filtered by reading the full text and excluding articles outside of the scope of our domain and which do not meet our criteria. Based on inclusion and exclusion criteria, 100 articles were selected and separated into five classes. The first class includes 39 articles (39%) consists of emotion, wherein various emotions are classified using artificial intelligence (AI). The second class includes 21 articles (21%) is composed of studies that use EEG techniques. This class is named 'brain condition'. The third class includes eight articles (8%) is related to feature extraction, which is a step before emotion classification. That this process makes use of classifiers should be noted. However, these articles are not listed under the first class because these eight articles focus on feature extraction rather than classifier accuracy. The fourth class includes 26 articles (26%) comprises studies that compare between or among two or more groups to identify and discover human emotion-based EEG. The final class includes six articles (6%) represents articles that study music as a stimulus and its impact on brain signals. Then, discussed the five main categories which are action types, age of the participants, and number size of the participants, duration of recording and listening to music and lastly countries or authors' nationality that published these previous studies. it afterward recognizes the main characteristics of this promising area of science in: motivation of using EEG process for measuring human brain signals, open challenges obstructing employment and recommendations to improve the utilization of EEG process.


Assuntos
Algoritmos , Inteligência Artificial , Eletroencefalografia , Emoções/classificação , Encéfalo/fisiologia , Humanos
6.
New Microbiol ; 40(4): 269-278, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28825446

RESUMO

Foodborne pathogens can be associated with a wide variety of food products and it is very important to identify them to supply safe food and prevent foodborne infections. Since traditional techniques are timeconsuming and laborious, this study was designed for rapid identification and clustering of foodborne pathogens isolated from various restaurants in Al-Qassim region, Kingdom of Saudi Arabia (KSA) using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Sixty-nine bacterial and thirty-two fungal isolates isolated from 80 food samples were used in this study. Preliminary identification was carried out through culture and BD Phoenix™ methods. A confirmatory identification technique was then performed using MALDI-TOF MS. The BD Phoenix results revealed that 97% (67/69 isolates) of bacteria were correctly identified as 75% Enterobacter cloacae, 95.45% Campylobacter jejuni and 100% for Escherichia coli, Salmonella enterica, Staphylococcus aureus, Acinetobacter baumannii, and Klebsiella pneumoniae. While 94.44% (29/32 isolates) of fungi were correctly identified as 77.77% Alternaria alternate, 88.88% Aspergillus niger and 100% for Aspergillus flavus, Penicillium digitatum, Candida albicans and Debaryomyces hansenii. However, all bacterial and fungal isolates were 100% properly identified by MALDI-TOF MS fingerprinting with a score value ≥2.00. A gel view illustrated that the spectral peaks for the identified isolates fluctuate between 3,000 and 10,000 Da. The results of main spectra library (MSP) dendrogram showed that the bacterial and fungal isolates matched with 19 and 9 reference strains stored in the Bruker taxonomy, respectively. Our results indicated that MALDI-TOF MS is a promising technique for fast and accurate identification of foodborne pathogens.


Assuntos
Bactérias/isolamento & purificação , Microbiologia de Alimentos , Fungos/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Bactérias/classificação , Bactérias/genética , Análise por Conglomerados , Fungos/classificação , Fungos/genética , Humanos , Restaurantes , Arábia Saudita , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/economia , Fatores de Tempo
7.
Phytopathology ; 104(12): 1289-97, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24941327

RESUMO

To develop an effective biocontrol strategy for management of Fusarium head blight on wheat caused by Fusarium graminearum, the bacterial biocontrol agent Pcho10 was selected from more than 1,476 wheat-head-associated bacterial strains according to its antagonistic activity in vitro. This strain was subsequently characterized as Pseudomonas chlororaphis subsp. aurantiaca based on 16S ribosomal DNA sequence analysis, assays of the BIOLOG microbial identification system, and unique pigment production. The major antifungal metabolite produced by Pcho10 was further identified as phenazine-1-carboxamide (PCN) on the basis of nuclear magnetic resonance data. The core PCN biosynthesis gene cluster in Pcho10 was cloned and sequenced. PCN showed strong inhibitory activity against F. graminearum conidial germination, mycelial growth, and deoxynivalenol production. Tests both under growth chamber conditions and in field trials showed that Pcho10 well colonized on the wheat head and effectively controlled the disease caused by F. graminearum. Results of this study indicate that P. chlororaphis subsp. aurantiaca Pcho10 has high potential to be developed as a biocontrol agent against F. graminearum. To our knowledge, this is the first report of the use of P. chlororaphis for the management of Fusarium head blight.


Assuntos
Antifúngicos/farmacologia , Fusarium/fisiologia , Controle Biológico de Vetores , Fenazinas/farmacologia , Doenças das Plantas/microbiologia , Pseudomonas/fisiologia , Triticum/microbiologia , Antibiose , Antifúngicos/química , Antifúngicos/isolamento & purificação , Sequência de Bases , Fusarium/citologia , Fusarium/efeitos dos fármacos , Dados de Sequência Molecular , Micélio , Fenazinas/química , Fenazinas/isolamento & purificação , Filogenia , Doenças das Plantas/prevenção & controle , Pseudomonas/química , Pseudomonas/genética , Pseudomonas/isolamento & purificação , Sementes/imunologia , Sementes/microbiologia , Análise de Sequência de DNA , Esporos Fúngicos , Tricotecenos/metabolismo , Triticum/imunologia
8.
Molecules ; 19(2): 2637-54, 2014 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-24566327

RESUMO

A general route for the synthesis of a novel class of pyridazin-3-one derivatives 3 by the reaction in acetic anhydride between 3-oxo-2-arylhydrazonopropanals 1 and some active methylene compounds like p-nitrophenylacetic acid and cyanoacetic acid was established. Under these conditions the pyridazin-3-one derivatives 3 were formed as the sole isolable products in excellent yield. The 6-acetyl-3-oxopyridazine derivative 3l was reacted with DMF-DMA to afford the corresponding enaminone derivative 4, which reacts with a variety of aminoazoles to afford the corresponding azolo[1,5-a]pyrimidine derivatives 5-7. Also, in order to explore the viability and generality of a recently uncovered reaction between 3-oxo-2-arylhydrazonopropanals and active methylene compounds, a variety of 2-amino-6-aryl-5-arylazo-3-aroylpyridines 16-19 were prepared by reacting 3-oxo-2-arylhydrazonopropanals with miscellaneous active methylene compounds like 3-oxo-3-phenylpropionitrile, hetaroylacetonitriles and cyanoacetamides. These 2-aminopyridine derivatives undergo smooth reactions with cyanoacetic acid that led to the formation in high yield of a new class of 1,8-naphthyridine derivatives 24. The structures of all new substances prepared in this investigation were determined by the different analytical spectroscopic methods, in addition to the X-ray crystallographic analysis.


Assuntos
Compostos Azo/síntese química , Piridazinas/síntese química , Piridinas/síntese química , Acetatos/química , Compostos Azo/química , Compostos Heterocíclicos/síntese química , Compostos Heterocíclicos/química , Estrutura Molecular , Piridazinas/química , Piridinas/química
9.
Microbiol Spectr ; 11(4): e0010823, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37318357

RESUMO

Botrytis cinerea causes gray mold on thousands of plants, leading to huge losses in production. Anilinopyrimidine (AP) fungicides have been applied to control B. cinerea since the 1990s. Although resistance to AP fungicides was detected soon after their application, the mechanism of AP resistance remains to be elucidated. In this study, a sexual cross between resistant and sensitive isolates was performed, and the genomes of parental isolates and progenies were sequenced to identify resistance-related single nucleotide polymorphisms (SNPs). After screening and verification, mutation E407K in the Bcmdl1 gene was identified and confirmed to confer resistance to AP fungicides in B. cinerea. Bcmdl1 was predicted to encode a mitochondrial protein that belonged to a half-type ATP-binding cassette (ABC) transporter. Although Bcmdl1 was a transporter, it did not mediate resistance to multiple fungicides but mediated resistance specifically to AP fungicides. On the other hand, reductions in conidial germination and virulence were observed in Bcmdl1 knockout transformants compared to the parental isolate and complemented transformants, illustrating the biological functions of Bcmdl1. Subcellular localization analysis indicated that Bcmdl1 was localized in mitochondria. Interestingly, the production of ATP was reduced after cyprodinil treatment in Bcmdl1 knockout transformants, suggesting that Bcmdl1 was involved in ATP synthesis. Since Mdl1 could interact with ATP synthase in yeast, we hypothesize that Bcmdl1 forms a complex with ATP synthase, which AP fungicides might target, thereby interfering with the metabolism of energy. IMPORTANCE Gray mold, caused by B. cinerea, causes huge losses in the production of many fruits and vegetables. AP fungicides have been largely adopted to control this disease since the 1990s, and the development of resistance to AP fungicides initiates new problems for disease control. Due to the unknown mode of action, information on the mechanism of AP resistance is also limited. Recently, mutations in mitochondrial genes were reported to be related to AP resistance. However, the mitochondrial process of these genes remains to be elucidated. In this study, we identified several AP resistance-related mutations by quantitative trait locus sequencing (QTL-seq) and confirmed that mutation E407K in Bcmdl1 conferred AP resistance. We further characterized the expression patterns, biological functions, subcellular localization, and mitochondrial processes of the Bcmdl1 gene. This study deepens our understanding of the mechanism of resistance to and mode of action of AP fungicides.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Fungicidas Industriais , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Fungicidas Industriais/farmacologia , Esporos Fúngicos/metabolismo , Virulência , Trifosfato de Adenosina , Doenças das Plantas , Farmacorresistência Fúngica
10.
Artigo em Inglês | MEDLINE | ID: mdl-37749966

RESUMO

INTRODUCTION: Keloids are pathologic conditions characterized by fibroblast hyper-proliferation and excess collagen deposition. Enalapril, one of the angiotensin-converting enzyme inhibitors, has recently been highlighted as a new therapeutic modality in treating keloids. This study evaluates the effectiveness of intralesional injection of enalapril versus triamcinolone acetonide (TAA) in keloids. METHODS: Forty patients with multiple keloids were enrolled in our study. Enalapril and TAA were injected intralesionally in one session per month for three sessions. The clinical outcomes were assessed via the Vancouver Scar Scale (VSS) and the Patient and Observer Scar Assessment Scale (POSAS). RESULTS: In both groups, according to VSS and POSAS, there was a high statistically significant difference (p-value ≤ 0.01) before treatment, at the end of each session, and 3 months after treatment. There was no significant difference between both groups regarding degree of improvement. Patients treated with TAA developed more significant complications than those in the enalapril group (p-value < 0.05). CONCLUSIONS: Both enalapril and TAA had the same clinical effect. Enalapril could be a safe alternative to steroids in the treatment of keloid and hypertrophic scars. Further studies on enalapril are needed on a large sample of patients with further focus on the mechanism of this innovative drug.


Assuntos
Cicatriz Hipertrófica , Queloide , Humanos , Injeções Intralesionais , Queloide/tratamento farmacológico , Triancinolona Acetonida/uso terapêutico , Enalapril/uso terapêutico , Cicatriz Hipertrófica/tratamento farmacológico
11.
Iran J Microbiol ; 15(3): 448-455, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37448674

RESUMO

Background and Objectives: 17 ß-estradiol (E2) is an important pollutant of the aquatic system. It is responsible for sexual disruptions in the majority of aquatic organisms. This study aimed to search for bacteria with high potential degradation of E2 as an important method for bioremediation. Materials and Methods: Sewage water samples were collected and treated to isolate bacterial strains which were identified by conventional methods and 16S ribosomal RNA gene sequence analysis. The biodegradation of E2 by the isolated strains was evaluated under different environmental conditions. Results: Two bacterial strains were recovered from sewage water samples and identified as Stenotrophomonas tumulicola and Serratia marcescens, (named ASc2 and ASc5 respectively). Co-culture of the two strains showed biodegradation of approximately 93.6 % of E2 (50 mg. L-1) within 48 hours. However, the biodegradation capacity of the same E2 concentration was 69.4% and 71.2% for ASc2 and ASc5 each alone, respectively. The optimum cultivation conditions for efficient E2 biodegradation by co-culture were 5% (v/v) inoculation volume with 50 mg. L-1 of E2 as the initial concentration at pH 7 and 30°C within 48 hours inoculation period. Conclusion: This study detected new bacterial strains that are capable of rapid degradation of estrogen as an environmental pollutant.

12.
ACS Omega ; 8(49): 47239-47253, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38107937

RESUMO

An efficient, microwave/ultrasound-irradiated synthesis of novel chromenopyrimidines has been established. 2-Amino-5-oxo-4-(thiophen-2-yl)-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile (1) underwent cyclization reactions with various assorted reagents under sustainable conditions to afford a family of fused pyrimidine derivatives. The proposed structures of the designed fused pyrimidines were confirmed by several spectral techniques. Moreover, the targeted pyrimidines were estimated for their in vitro cytotoxic activities toward three carcinoma cell lines: breast (MCF7), hepatocyte (HepG2), and lung (A549) cancer cell lines, as well as one noncancerous cell line (MCF-10A). Structure-activity relationship (SAR) analyses revealed that derivatives 3 and 7 exhibited the highest potency in inhibiting the growth of cancer cells tested in vitro. Particularly, 3-amino-4-imino-5-(thiophen-2-yl)-3,4,5,7,8,9-hexahydro-6H-chromeno[2,3-d]pyrimidin-6-one (3) displayed a robust impact with IC50 values ranging from 2.02 to 1.61 µM. Interestingly, compound 3 was observed to have low cytotoxicity toward noncancerous cell (MCF-10A) compared to the standard drug (Doxorubicin). Further, quantum chemical computations of the designed molecules utilizing density functional theory (DFT) were conducted and shown to be compatible with the observed antiproliferative properties. Thorough docking investigations revealed that the assembled compounds possess exceptionally low binding energies toward our three selected proteins: 4b3z-Lung, HepG2-2JW2, and 6ENV-MCV-7. Based on these intriguing results, compound 3 could be further evaluated for preclinical screening, potentially paving the way for its utilization as a promising cancer treatment.

13.
Molecules ; 17(6): 6362-85, 2012 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-22634845

RESUMO

The 4-thiazolidinones 3a-d were used as a key intermediates for the synthesis of 2-arylimino-5-arylidene-4-thiazolidinones derivatives 7a­p via nucleophilic addition reactions with the arylidene malononitrile. Moreover the 4-thiazolidinones 3a and 3c condensed with the DMF-DMA to form the corresponding enamines 8 and 9 depending on the reaction conditions. Otherwise the 4-thiazolidinone 3b reacts regioselectively with DMF-DMA to afford the enaminones 10 and 11, respectively. The latter reacts with many heterocyclic amines affording polyfunctionally substituted fused pyrimidine derivatives 13-18. The enamine 8b was also reacted with the 3-amino-1,2,4-triazole to afford the acyclic product 19, which could not be further cyclized to the corresponding tricyclic system 20. Moreover the 4-thiazolidinone 3c reacted with the benzenediazonium chloride to afford the arylhydrazones 12. The X-ray single crystal technique was employed in this study for structure elucidation and Z/E potential isomerism configuration determination. The X-ray crystallographic analyses of eight products could be obtained, thus establishing with certainty the structures proposed in this work.


Assuntos
Pirimidinas/síntese química , Tiazolidinas/síntese química , Compostos Heterocíclicos/síntese química , Compostos Heterocíclicos/química , Ressonância Magnética Nuclear Biomolecular , Pirimidinas/química , Tiazolidinas/química
14.
Sci Rep ; 12(1): 12502, 2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35869107

RESUMO

Pathogenic bacteria cause disease outbreaks and threaten human health, prompting the research on advanced detection assays. Herein, we developed a selective molecular imprinted aptasensor for sensitive and prompt quantitation of Staphylococcus aureus (S. aureus) bacteria. The aptasensor was constructed by immobilization of aptamer on gold nanoparticles modified magnetic nanoparticles (apt-AuNPs@ Fe3O4). A functional monomer (o-phenylenediamine, o-phen) was electro-polymerized on the surface of the as-synthesized nanocomposite in the presence of a template (S. aureus). After removing S. aureus, the formed imprinted sites were available to extract pathogenic bacteria from complicated matrices. The surface morphology of the as-fabricated nanocomposites was characterized using different spectroscopic and electrochemical methods. Moreover, we thoroughly evaluated factors affecting the synthesis and determination procedures. The molecular imprinted aptasensor exhibited a wide linear range of 101-107 CFU mL-1 with a Limit of Detection, LOD (signal to noise = 3) of 1 CFU mL-1. The aptasensor detected S. aureus in milk, conduit water, and apple juice samples with good recoveries % and satisfactory relative standard deviations (RSDs %) values.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Infecções Estafilocócicas , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Ouro/química , Humanos , Limite de Detecção , Nanopartículas Metálicas/química , Infecções Estafilocócicas/diagnóstico , Staphylococcus aureus
15.
AMB Express ; 12(1): 53, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35532863

RESUMO

Psychrotrophic Pseudomonas is one of the significant microbes that lead to putrefaction in chilled meat. One of the biggest problems in the detection of Pseudomonas is that several species are seemingly identical. Currently, antibiotic resistance is one of the most significant challenges facing the world's health and food security. Therefore, this study was designed to apply an accurate technique for eliminating the identification discrepancy of Pseudomonas species and to study their resistance against various antimicrobials. A total of 320 chicken meat specimens were cultivated, and the isolated bacteria' were phenotypically recognized. Protein analysis was carried out for cultured isolates via Microflex LT. The resistance of Pseudomonas isolates was recorded through Vitek® 2 AST-GN83 cards. Overall, 69 samples were identified as Pseudomonas spp. and included 18 Pseudomonas lundensis (P. lundensis), 16 Pseudomonas fragi (P. fragi), 13 Pseudomonas oryzihabitans (P. oryzihabitans), 10 Pseudomonas stutzeri (P. stutzeri), 5 Pseudomonas fluorescens (P. fluorescens), 4 Pseudomonas putida (P. putida), and 3 Pseudomonas aeruginosa (P. aeruginosa) isolates. Microflex LT identified all Pseudomonas isolates (100%) correctly with a score value ≥ 2.00. PCA positively discriminated the identified isolates into various groups. The antimicrobial resistance levels against Pseudomonas isolates were 81.16% for nitrofurantoin, 71% for ampicillin and ampicillin/sulbactam, 65.22% for cefuroxime and ceftriaxone, 55% for aztreonam, and 49.28% for ciprofloxacin. The susceptibilities were 100% for cefotaxime, 98.55% for ceftazidime, 94.20% for each piperacillin/tazobactam and cefepime, 91.3% for cefazolin. In conclusion, chicken meat was found to be contaminated with different Pseudomonas spp., with high incidence rates of P. lundensis. Microflex LT is a potent tool for distinguishing Pseudomonads at the species level.

16.
Chemosphere ; 303(Pt 1): 134969, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35588881

RESUMO

A systematic investigation on the isotopic and elemental signature, for both stable and radioactive elements, and mineral contents was performed to examine the characteristics of subsurface formations collected at different depths between 3.962 km and 4.115 km around deep-laying coal seams located under the Marmarica plateau in Egypt. Concentrations of major and minor oxides (Na2O, MgO, Al2O3, SiO2, SO3, K2O, CaO, TiO2, MnO, ΣFeO + Fe2O3, SrO, ZrO2, and BaO) were determined by X-ray fluorescence and dependencies among these concentrations revealed the type and sort of the formations. Organic contents were determined by Fourier Transform infrared spectroscopy to investigate the variation of the CO/CC bonding ratio with depth. Rare earth elements (REE), specifically Y, Sc, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu were determined by inductively coupled plasma mass spectrometry while actinoids were detected by the radioactive decay of its daughter nuclei. The results showed a high trapping of REE elements and actinoids in layers above the coal seams which indicates the occurrence of aqueous flow followed by possible sorption in these layers. The mobility of the fluid was investigated using the process radioactive decay series between Ra226 and Ac228 from one side and their daughters from the other side.


Assuntos
Carvão Mineral , Metais Terras Raras , Carvão Mineral/análise , Isótopos/análise , Metais Terras Raras/análise , Minerais , Dióxido de Silício
17.
Diagnostics (Basel) ; 12(11)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36359489

RESUMO

Raw ground meat is known as a transmission vehicle for biological agents that may be harmful to human health. The objective of the present study was to assess microbiological quality of the ground meats. A total of 280 samples of local and imported chilled meats were randomly collected from retail shops in Buraydah City, Saudi Arabia. The meat samples were microbiologically analyzed using standard methods, peptide mass fingerprinting (PMF) technique, MicroScan Walkaway System (MicroScan) and qPCR System. The imported meat was more bacterially contaminated than local meat, with variable contamination degrees of Staphylococcus aureus (40.33%), Escherichia coli (36.13%), Hafnia alvei (7.56%), Pseudomonas spp. (6.72%), Salmonella spp. (5.88%) and Aeromonas spp. (3.36%). PMF verified all the isolated bacteria by 100%, compared to 75-95% achieved by MicroScan. The gene encoding flagellin (fliC) was recognized in 67.44% of E. coli strains, while the thermonuclease (nuc) and methicillin resistance (mecA) genes were detected in 100% S. aureus and 39.6% of methicillin-resistant S. aureus (MRSA) strains, respectively. The S. aureus and E. coli strains were highly resistant to multiple antibiotics (e.g., ampicillin, amoxicillin-clavulanic acid and cephalothin). For identifying various foodborne pathogens, PMF has been recognized as a powerful and precise analytical method. In light of the increasing use of PMF to detect multidrug-resistant bacteria, this study emphasizes the need for improved ways of treating and preventing pathogens, as well as setting up monitoring systems to guarantee hygiene and safety in meat production.

18.
Molecules ; 16(5): 3723-39, 2011 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-21544037

RESUMO

1,2,3-Triazolo[4,5-b]pyridines and pyrazolo[4,3-b]pyridines can be readily prepared via cyanoacetylation reactions of 5-amino-1,2,3-triazoles 1a,b and 4-amino- pyrazole 2 followed by subsequent cyclization of the formed cyanoacetamides. Reactions of amines 1a,b with a mixture of p-nitrophenylacetic acid and acetic anhydride under microwave irradiation conditions afforded the corresponding amides 15a,b that underwent cyclization to form 1,2,3-triazolo[4,5-b]pyridines 16a,b upon heating in DMF solutions containing sodium acetate. Reactions of 1a,b with active methylene compounds, including 17a-c, in the presence of zeolites as catalyst also afforded 1,2,3-triazolo[4,5-b]pyridine derivatives 20a-f via the intermediacy of triazole derivatives 19 and not 18.


Assuntos
Acetatos/química , Aminas/química , Nitrilas/química , Piridinas/química , Piridinas/síntese química , Triazóis/química , Acilação , Estrutura Molecular , Nitrofenóis/química , Zeolitas/química
19.
Saudi J Biol Sci ; 28(1): 693-706, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33424357

RESUMO

The quantification, localization, production, function, and regulation of irisin/FNDC5 in camel species have not been previously studied. The objective of this study was to detect the irisin content in Arabian camel blood and tissues and study the gene expression of FNDC5 and PGC-1α in camel skeletal muscles and white adipose tissue depots under basal conditions. To monitor if exercise influences blood and tissue irisin protein levels as well as FNDC5 and PGC-1α gene expression levels, we analyzed irisin concentrations in the serum, skeletal muscles (soleus and gastrocnemius), and white adipose tissues (hump, subcutaneous, visceral, epididymal, and perirenal) in both control (n = 6) and exercised group (n = 6) using ELISA and determined the cellular localization of irisin/FNDC5 and the mRNA levels of FNDC5 and PGC-1α in skeletal muscles and adipose tissues via immunohistochemistry and real-time PCR, respectively. The possible regulatory roles of exercise on some hormones and metabolites as well as the detection of links between serum irisin and other circulating hormones (insulin, leptin, and cortisol) and metabolites (glucose, free fatty acids, triglycerides, and ATP) were explored for the first time in camels. Our results indicated that exercise induces tissue-specific regulation of the camel irisin, FNDC5, and PGC-1α levels, which subsequently regulates the circulating irisin level. Significant associations were detected between the levels of irisin/FNDC5/PGC-1α in camels and the metabolic and hormonal responses to exercise. Our study suggested that irisin regulates, or is regulated by, glucose, FFA, insulin, leptin, and cortisol in camels. The novel results of the present study will serve as baseline data for camels.

20.
ACS Omega ; 6(24): 16086-16099, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34179654

RESUMO

An efficient high-pressure-assisted trifluoroacetic acid-catalyzed protocol for synthesizing unreported novel pyrido[1,2-b][1,2,4]triazine and pyrido[1',2':2,3][1,2,4]triazino[5,6-b]indole derivatives has been established. This strategy includes the condensation reactions of various 1-amino-2-imino-4-arylpyridine-3-carbonitrile derivatives with indoline-2,3-dione (isatin) derivatives and α-keto acids such as pyruvic acid and phenylglyoxylic acid. This strategy includes utilizing the Q-tube reactor as an efficient and safe tool to conduct these reactions under high-pressure conditions. In addition, trifluoroacetic acid was used to induce this transformation. In this research, conducting the targeted reactions under high pressure using the Q-tube reactor was found to be superb in comparison to that under the traditional refluxing conditions. X-ray single-crystal analysis was utilized in this study to authenticate the structure of the synthesized products.

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